Drawer slide assembly

ABSTRACT

A drawer slide assembly comprises: an outer slide; an intermediate slide; an inner slide having a protruding block mounted on one end thereof; and a sequence control device to enable the outer slide, the intermediate slide, and the inner slide to be pulled out sequentially. The intermediate slide and the inner slide are mounted inside the outer slide and the inner slide is mounted inside the intermediate slide. A guide plate is mounted on the outer slide. A positioning trench having an expansion trench is formed on a top surface of the guide plate. A shrinking opening is formed between the expansion trench and the positioning trench. An elastic restriction means having a pair of oppositely extended stopping means is mounted on the intermediate slide. As a result, the outer slide is prevented from being damaged by heavier weight.

FIELD OF THE INVENTION

The present invention relates to a slide assembly adapted for use with a drawer, and more particularly to drawer slide assembly having a sequence control device for providing the pulling process with better moment, thereby dispersing the supported weight uniformly, smoothing the pulling process, and prolonging lifetime.

BACKGROUND OF THE INVENTION

The conventional slide assembly of a conventional drawer is composed of an outer slide, an intermediate slide, and an inner slide. When the drawer is pulling out, the drawer first drives the inner slide outward in a first-stage pulling step and subsequently drives the intermediate slide in a second-stage pulling step for pulling out the drawer completely. In the conventional pulling process, the inner slide is first pulled out completely or pulled out partially followed by pulling out the intermediate slide simultaneously. Because the stress, which is formed in the shifting process of the inner slide and applied to the outer slide is non-uniform, the lifetime of the outer slide is thus shortened.

In view of the stress problem caused by the sequence of pulling out the slides, the related industrial manufacturers have developed sequence control mechanisms as disclosed in U.S. Pat. No. 5,757,109 and U.S. Pat. No. 6,685,288, wherein the sequence control mechanisms are mounted between the slides for providing a specific pulling sequence for the inner slide and the outer slide.

SUMMARY OF THE INVENTION

Because the conventional structure suffers from non-uniform stress, which causes damage and deformation easily, and has short lifetime, the present inventor improves the conventional drawer slide assembly for satisfying the requirements for practical use.

It is a major object of the present invention to provide a sequence control device between the slides so as to apply uniform stress to the outer slide by the use of the two-stage pulling process, whereby the shortened lifetime caused by the larger stress can be avoided.

It is another object of the present invention to provide a sequence control device for truly pulling out the drawer by the two-stage pulling process, wherein an inner slide drives an elastic restriction means of an intermediate slide when the drawer is pulling out such that these two slides can be shifted synchronously to avoid interference with each other, thereby smoothing the pulling process.

It is still another object of the present invention to mount a guide plate on the outer slide so as to fix the elastic restriction means, which is coupled with the intermediate slide, when the intermediate slide, which is pulled out, reaches the location of the guide plate, thereby enabling the inner slide to be pulled out continually.

It is a further object of the present invention to provide a plastic sequence control device for the drawer slide assembly to avoid the friction among the metals, thereby prolonging the lifetime of the drawer slide assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a three-dimensional view of the present invention.

FIG. 2 is a three-dimensional, exploded view of the present invention.

FIG. 3 is a three-dimensional, exploded view showing the sequence control device of the present invention.

FIG. 4 is a three-dimensional, exploded view taken from another angle for showing the sequence control device of the present invention.

FIG. 5 is a three-dimensional, assembled view showing the sequence control device of the present invention.

FIG. 6 is a top plan view showing that the elastic restriction means is coupled with the guide plate.

FIG. 7 is a schematic view taken in the arrow direction of line A-A in FIG. 6.

FIG. 8 is a view showing the process for pulling out the drawer slide assembly of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1 through FIG. 3, a drawer slide assembly of the present invention comprises an outer slide 1, an intermediate slide 2, and an inner slide 3, wherein the intermediate slide 2 and the inner slide 3 are located in the outer slide 1. Besides, a sequence control device 4 is mounted between the outer slide 1 and the intermediate slide 2.

Three positioning holes 11, 12, and 13 and a protruding buckle 14 are formed on the proper positions of the above-mentioned outer slide 1 for holding a guide plate 41 of the sequence control device 4. A buckling trench 21 is formed on one end of the intermediate slide 2 for holding an elastic restriction means 42 of the sequence control device 4. Besides, the inner slide 3 is mounted inside the intermediate slide 2, wherein a protruding block 31 is extendedly mounted on one end of the inner slide 3. In addition, a plastic sleeve 32 is mounted to sleeve the protruding block 31 for reducing friction among metals, thereby elongating the lifetime of the drawer slide assembly. When assembled, these three slides can be pulled out in sequence by using the sequence control device 4.

Referring to FIG. 2 through FIG. 5, the structure of the sequence control device 4, which is mounted between the slides, is shown. The sequence control device 4 comprises the guide plate 41 and the elastic restriction means 42, wherein the guide plate 41 is located on the outer slide 1. Besides, the guide plate 41 can be made of plastic material or molded integrally with the outer slide 1. Several positioning blocks 411, 412, and 413 are mounted on the backside of the guide plate 41, and a pair of coupling means 416 is extended downward from one side of the guide plate 41. A positioning trench 414 having an expansion trench 415 is formed on a top surface of the guide plate 41. As a result, the coupling means 416 can be coupled with the protruding buckle 14 by coupling the positioning blocks 411, 412, and 413 of the guide plate 41 with the positioning holes 11, 12, and 13 of the outer slide 1 so as to fix the guide plate 41.

A pair of buckling means 422, a pair of stopping means 423, a pair of hooks 424, and several positioning blocks 425 are integrally formed on a main body 421 of the elastic restriction means 42, wherein these positioning blocks 425 and the hooks 424 are mounted on the bottom of the elastic restriction means 42 for fixing the elastic restriction means 42 in the buckling trench 21 of the intermediate slide 2. The elastic restriction means 42 is designed to be hollowed out except the connection portions among the components so as to provide the elastic restriction means 42 with elasticity. Two lateral fins 426, which are mounted on both sides of the main body of the elastic restriction means 42, respectively, are bended upward. These lateral fins 426 are also connected to the buckling means 422 and the stopping means 423 such that they can be driven by one another, wherein the buckling means 422 are integrally connected to the upper portions of the main body 421 of the elastic restriction means 42 and the stopping means 423 are integrally, oppositely extended from the lower portions of the buckling means 422. When the stopping means 423 are working, the buckling means 422 are driven by the stopping means 423 so as to further drive the lateral fins 426.

Referring to FIG. 5 through FIG. 8, the pulling status of the slide assembly is shown. If there is a need to open the drawer, the intermediate slide 2 and the inner slide 3 are first pulled out together such that the plastic sleeve 32, which is mounted on the inner slide 3, is shifted to touch the buckling means 422 of the elastic restriction means 42. As a result, the intermediate slide 2 and the inner slide 3 can be shifted at the same time to avoid interference with each other. When the intermediate slide 2 and the inner slide 3 are shifting simultaneously, the outer slide 1 will bear more uniform stress. As a result, the outer slide will not suffer from the conventional non-uniform stress, which occurs while the conventional inner slide is shifting alone, and which shortens the lifetime.

After the intermediate slide 2 and outer side 3 are pulled out for a distance simultaneously, the intermediate slide 2 is restricted by the guide plate 41, which is located on the outer slide 1. After the guide plate 41 is in contact with the elastic restriction means 42, the stopping means 423 of the elastic restriction means 42 will be guided into the expansion trench 415 of the guide plate 41. In addition, a shrinking opening 417 is formed between the expansion trench 415 and the positioning trench 414. When the stopping means 423 is guided to pass the shrinking opening 417, the shrinking opening 417 will oppress the stopping means 423 inward so as to expand the buckling means 422 outward for forming a tunnel (shown in FIG. 7). At this moment, the plastic sleeve 32, which is mounted on the inner slide 3, is allowed to pass the buckling means 422, and the stopping means 423 of the elastic restriction means 42 are restricted by the positioning trench 414 to enable the intermediate slide 2 to be positioned on the outer slide 1 after being pulled out for a certain distance. At this moment, only the inner slide 3 can be pulled out such that the drawer can be opened fully by pulling out the inner slide 3 completely.

During the two-stage pulling process, the intermediate slide 2 and the inner slide 3 are both utilized to conduct the first-stage pulling step for obtaining the ability to bear heavier weight. Because the inner slide 3 and the intermediate slide 2 are pulled out together, the stress applied to the outer slide 1 is more uniform. As a result, the outer slide is provided with longer lifetime.

By using the sequence control device 4, which is mounted between the slides, the slides can be pulled out sequentially. Similarly, the inner slide 3 and the intermediate slide 2 can be folded sequentially by using the sequence control device 4. As a result, the drawer slide assembly of the present invention satisfies all requirements for a patent. While the preferred embodiment of the invention has been set forth for the purpose of disclosure, modifications of the disclosed embodiment of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments, which do not depart from the spirit and scope of the invention. 

1. A drawer slide assembly comprising: an outer slide having a guide plate on which a positioning trench having an expansion trench is formed on a top surface thereof; an intermediate slide on which an elastic restriction means having a pair of oppositely extended stopping means is mounted; an inner slide having a protruding block extending from one end thereof; and a sequence control device to enable the outer slide, the intermediate slide, and the inner slide to be pulled out sequentially, wherein the intermediate slide and the inner slide are mounted inside the outer slide and the inner slide is mounted inside the intermediate slide, and wherein a shrinking opening is formed between the expansion trench and the positioning trench.
 2. The drawer slide assembly of claim 1, wherein the guide plate is a plastic sleeve that fixedly mounts on the outer slide.
 3. The drawer slide assembly of claim 1, wherein the guide plate is molded integrally with the outer slide.
 4. The drawer slide assembly of claim 1, wherein a plurality of positioning blocks are mounted on the backside of the guide plate and a pair of coupling means is extended downward from one side of the guide plate such that the coupling means can be coupled with the outer slide by coupling the positioning blocks with a plurality of positioning holes of the outer slide so as to fix the guide plate.
 5. The drawer slide assembly of claim 1, wherein a plurality of positioning blocks and a pair of hooks are mounted on the bottom of the elastic restriction means for fixing the elastic restriction means on the intermediate slide.
 6. The drawer slide assembly of claim 1, wherein a pair of buckling means, a pair of stopping means, a pair of hooks, and a plurality of positioning blocks are integrally formed on the elastic restriction means, two lateral fins are bended upward from both sides of a main body of the elastic restriction means, respectively, and connected to the main body, the buckling means, and the stopping means, wherein the buckling means, which are mounted on the elastic restriction means, are integrally connected to the main body such that the buckling means are driven by the stopping means so as to further drive the main body and the lateral fins when the stopping means are working.
 7. The drawer slide assembly of claim 6, wherein the main body, the buckling means, the stopping means are integrally connected with one another and an upper portion of the elastic restriction means is designed to be hollowed out so as to provide with elasticity.
 8. The drawer slide assembly of claim 1, wherein a plastic sleeve is mounted to sleeve the protruding block extending from the inner slide. 